package Java9_8;

import java.util.Scanner;

public class Test_5 {
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        System.out.println("请输入一个字符串");
       String a=in.next();
       String b=a.replaceAll("\\D","");
        System.out.println(b);
    }
}
